Hydrocarbon exploration and production wells require boreholes into the earth. With traditional single bore wells many structures were needed at the surface to service the well (derek, etc.) More recently multilateral wellbores have become popular since they reduce the surface impact and are more economically favorable to operate. In many multilateral junctions it is desirable to have a junction system in place. These are often run in on a work string to be placed correctly.
Lateral junction systems, and particularly the hook hanger liner system commercially available from Baker Oil Tools, Houston, Tex. and commonly known as the hook hanger, is an oft-used junction system in multilateral wellbores. The system provides a great many benefits to the art and works very well when run on rotatable tubing. Providing that alignment of the bent sub of the system is within about ±60° to 90° of the casing exit window, the system will exit the window and the liner and the hook hanger will continue to advance. Where the bent sub is outside of the about ±60° to 90° from alignment with the casing exit window, the bent sub will pass down the primary borehole, usually to a restriction. In this event, the system is pulled back, rotated from the surface and advanced again. This process is repeated until the bent sub exits the target window. Later in the operation, as the hook hanger itself draws near the window, the hook of the hook hanger must be aligned within about ±30° of the exit window so that it will self align at the bottom vee of the window. If the hook is not aligned within about ±30° of the window then the hook will not self align and it is necessary to pull the system back uphole until the hook is above the level of the lateral and rotate the string for another try. As is well known commercially, the system works very well for its intended purpose when run on rotatable tubing. Unfortunately, however, a drawback of the system becomes apparent when it is desired or required to run coil tubing instead of a standard work string. The drawback is experienced because of an inherent issue of coil tubing. Coil tubing cannot be rotated. It is therefore not possible to reposition a hook hanger product that does not by luck hit the exit window on the first pass. Heretofore, then, it has simply been impractical to attempt a use of a hook hanger product where coil tubing is the venue.